$w:50px;
$h:30px;
$bg:yellow;

#box3{
  height:$w;
  width: $h;
  background: $bg;
  display: flex;
  backface-visibility: hidden;
  background: url("../imgs/21.gif") no-repeat 100%;
}

/*
#box3{
  height:$w;
  width: $h;
  background: $bg;
  display: flex;
  backface-visibility: hidden;
}*/
